Field
Embodiments of the present invention relate to a semiconductor memory device.
Description of the Related Art
A flash memory is a semiconductor memory device known for its low cost and large capacity. One example of a semiconductor memory device to replace the flash memory is a variable resistance type memory (ReRAM: Resistance RAM) which employs a variable resistance film in its memory cell. The ReRAM can configure a cross-point type memory cell array, hence can achieve an increased capacity similarly to the flash memory. Moreover, in order to further increase capacity, there is also being developed a ReRAM having a so-called VBL (Vertical Bit Line) structure in which bit lines which are selection wiring lines are arranged in a perpendicular direction to a semiconductor substrate.